Thread cutter device for sewing machines



Dec. 25, 1934.

J. GOULDBOURN THREAD CUTTER DEVICE FOR SEWING MACHINES Filed Aug. 29,1933 5 sheets-sheet 1 Dec. 25, 1934. J, OULDBO'URN I 1,985,605

THREAD CUTTER DEVICE FOR SEWING MACHINES Filed Aug. 29, 1935 5 Sheets-Sheet 2 10 e .A o O as 8+ 20 90 v 6+ -62= s 7g 4 O o Z6 C. l (9 E I 7ZMW Dec. 25, 1934. J, GOULDBOURN 1,985,605

THREAD CUTTER DEVICE FOR SEWING MACHINES Filed Aug. 29, 1935 5Sheets-Sheet 4 a so milk/ M M M Dec. 25, 1934. J. GOULDBOURN 1,985,605

' THREAD CUTTER DEVICE FOR SEWING MACHINES Filed Aug. 29, 1933 5Sheeis-Shet 5 \ixfi 117 11's 1 Mtrwss Patented Dec. 25, 1934- 1 NITED -ET messes PATENT OFFICE THREAD CUTTER DEVICE FOR SEWING MACHINES 1'9Claims. (C1. lib-252 This invention relates to sewing machines-and isconcerned particularly with thread cutting and thread holding devicesfor lockstitch outsole shoe sewing machines. From certain of itsaspects, the invention may be consideredas being concerned withimprovements in the invention set 'forth in U. S. Patent No. 1,683,689granted to Alfred R. 'Morrill, dated September 11,1928; The object ofthe invention is to simplify and improve the construction 'andoperationof thread cutting and manipulating devices "heretofore employed forterminating a seam on a sewing machine of the type referred to.

One feature of the invention contemplates the provision in a lockstitchsewing machine of a cutter adapted to out both needle and shuttlethreads above the surface of the work at the side engaged by the presserfoot of the machine. Another feature of the invention comprises a needlethread end gripper located on the opposite side of'the work and adaptedto hold the cut supply end of the needle thread, and means for pullingthe cut end to a correct position after the'cutting operation.

Theabove and other features of the invention will be evident to thoseskilled in the art from the following description and drawings of anillustrative form of device according to the in-' vention. v

In the drawings Figure l is a view in fron't elevation of a portion of amachine illustrating the features of the invention; Figure 2 is a viewin side elevation ofthe machine, looking from the right; Figure 3 is aview in front. elevation f certain parts of the machine; Figure 4 is a,

plan view illustrating the operation of the thread severing andmeasuring mechanism of the machine; Figure 5 is a partial sectional Viewin side elevation of the parts looking from the right of Figure 3 andillustrating'the thread severing operation; Figure 6 is a similar viewon an en-- larged scale; Figure 7 is a plan View on an enlarged scale ofa portion of the worksupport and the thread holding means arrangedthere-- on; Figure 8 is a view in elevation of the parts shown in Figure*7; Figure 9 is a plan viewon'a similar scale of the presser foot;Figure lll'lis a view looking from the right of the presser' foot;Figure 11 is a plan view of a work support embodying amodified form ofthe invention ap-- plicable to the present machine; and Figure 12 is aview in section, taken along the-line 12--12' of Figure 11,illustrating-the operation: clothe machinewith the modificationindicated in Figure ll.

The machine illustrated in the drawings is a lockstitch outsole stitchercomprising a curved hook needle 2, acurved awl 4, a work support 6, apresser foot 8, a shuttle 1'0 and other devices for manipulating thethreads in operating upon a shoe supported in the machine, similar tothose of the machine described in the Morrill patent, above referred'to.The operating parts ofthe machine are driven by a belt 12 surrounding "adriving pulley, l4 rotatably mounted on a cam shaft '16. The drivingpulley is connected and disconnectedfrom the cam shaft to drive the machineand permit it to come to, rest by the operation of a driving andstopping mechanism actuated by a treadle operated rod '18, a bell cranklever 20 connectedbetween the rod 18 and the hub of the pulley 14, andother controlling connections; The' driving and stopping mechanism isarranged to bring the machine to rest at a definite point in the cycleof operation withthe needle, awl, and 'presse'r "foot disengaged fromthe work. To permit the threads to be cut readi ly after the machine "isbrought to rest, the needle loop'is pulled only partway down towards thework at the side engaged by the presser foot so that 'a'portion of theneedle thread surrounding the shuttle thread extends above the worksurface, as described in the U. S. patent to Ashworth No. 1,519,652,dated'Deceniber 16, 1924.

According to the present invention a single cutting blade, indicated at22, is movably mounted on the machine for severing both threads abovethe surface of the Work engaged by the presser foot. To providesufficient thread for the initial stitch one new seam, a shuttle threadpull-'oficomes into operation, cutting blade 22 severs the threads, toengage the thread extending between the shuttleand the work;

The thread cutter knife blade '22 is formed at the lower end of aninclined rod 24 slidin'gly mounted at its upper end in a bracket 26pivoted on a horizontal shaft 28, the shaft being supported on themachine frame.

just before the The upper end of the rod '24 has a sloping cam face 30at its front side I .Wh'ich bears against a 1131132 rotating on a shaftonthe frame of the machine. The rod 24 is maintained in engagement-withtheroll 32 at all times by a spring plunger 34 bearing on the also hassecured to it a pinion member 38 env gaged by a segment 40 secured to ahorizontal rock shaft 42. The right end of the rock shaft 42 carries anarm 44 pivotally connected to a treadle operated rod 46, so thatdownward movement of the treadle rod causes the thread cutter 22 to movedownwardly and rearwardly against the work beneath the raised presserfoot. The treadle (not shown) connected to the treadle rod 46 may, forconvenience, be placed close alongside the machine starting treadlewhich is connected to the rod 18, so that it may be operated by the samefoot which the operator uses in con trolling the machine.

The shuttle thread pull off, indicated at 48, is best shown in Figures 5and 6, and acts not only to measure thread from the shuttle, but also todeflect threads to one side of the seam where movement of the threadcutter knife 22 against the work will more effectively sever thethreads, using the shoe sole as a cutting block. The shuttle thread pulloff 48 is formed with a sleeve portion surrounding the lower end of thethread cutter rod 24 and sliding loosely thereon. A pin 49 on the rodextends through a slot formed on the sleeve to prevent rotation of thesleeve on the rod, and the lower end of the sleeve portion terminates ina foot member which engages the shuttle thread as the sleeve descendsand moves rearwardly with the lower end of the cutter rod. The footmember of the pull or? 48 cooperates with the presser-foot while inraised position to pull off the required amount of thread from thebobbin. This amount may be variedby adjusting the position of the roll32 in a vertical direction whereby the position to which the pull offmoves rearwardly in descending after having engaged the thread may bechanged.

In addition to measuring off and deflecting thread, the pull off device48 also acts to urge the shuttle thread behind a spring catch 50 in thepresser foot to insure that the shuttlethread will extend in a directionin which it will correctly be engaged by the loop of needle threadpassed over it when a new seam is started. The shuttle thread pull 011,as indicated in Figure -9 by the dot and dash lines, has a fingerportion 52 formed on its left side rear lower end which is arranged toengage the thread and urge it to the right into a position in which itwill, as the foot portion of the pull off moves rearwardly, be forcedinto a slot 54 formed in the presser foot. The spring catch 50 is in theform of a sliding pin projecting at one end into the slot and acting totrap the thread behind it. To urge the catch pin towards the slot, aspring member 56 secured at one end to the presser foot yieldinglyengages the pin at its other end.

When the cutter rod 24 moves downwardly and rearwardly as in cutting thethread, the required amount of shuttle thread is pulled off and urgedinto the slot in the presser foot. Thereafter, the pull off remainsstationary while the rod 24 completes its stroke, the pull off slidingon the rod against the yielding pressure of a spring 58 contained withinthe sleeve portionof the pull off and compressed by; a shoulder on therod 24. The cutter blade 22 is thus permitted to come into engagementwith the needle loop and shuttle thread of the last formed stitch asclose as possible to the work so that a com-- plete finished seam notrequiring hand trimming results.

In severing the shuttle and needle threads close to the side of the workon which the shuttle is located, as with use of the machine described inthe patent to Ashworth, above identified, the operator ordinarily inwithdrawing the work from the machine leaves a length of needle threadcorresponding to the thickness of the shoe sole projecting above thework table. This length of thread, on starting the machine on a newseam, becomes clamped between the work table and the work so that afterthe new seam is completed, a trimming operation is required. To obviatethe necessity of trimming the needle thread at the leading end of theseam, in the present machine means is provided for retracting the needlethread before a new shoe is located on the work table and for holdingthe severed end of the thread remaining in the machine at apredetermined position in the work table where it may not be clamped byvthe work.

The means for retracting the needle thread comprises a thread pullerstud 60, extending horizontally from an arm 62 secured to a shaft 64,rotatably mounted in bearings on the machine frame. The stud when theshaft 64 is rotated, engages the needle thread, indicated at 66, andwithdraws a length thereof by moving it between a pin 68 mountedconcentrically at the end of the shaft 64 and a fixed pin 70. Thisoperation occurs after the thread cutter severs the threads and thetreadle actuated rod 46 is being released. When the treadle rod isreleased, a spring '72 surrounding the rod and acting between a collaron the rod and the frame of the machine raises the rod to retract thethread cutter rod 24 into an inactive position, shown in Fig. 1. Inmoving upwardly a shoulder 74 (Fig. 5) on the side of the rod engages apawl 76 fixed to a pivot 78 rotatable in one end of a lever 80. As therod 46 continues to rise, the lever 80 rotates about a fixed shaft82causing a segment 84 formed on one arm of the lever to rock a segment86 fixed to the shaft 64 which operates the thread retracting device.The retracting device is moved to its extreme position and againreturned to normal position during the upward movement of the treadlerod 46 which continues until a lever 88 secured to the pawl shaft 78strikes the lower end of a set screw 90 carried by the frame of themachine. When this occurs, the shaft '78 carrying the pawl 76 is rockedin a direction to release the pawl from the shoulder 74 on the rod 46,and a spring 92 connected to the lever 80 returns the lever to itsinitial position where it is brought to rest by contact with a secondset screw 94. The amount of needle thread retracted from the work may besuitably regulated by adjusting the set screws 90 and 94 so that variedamounts of movement may be imparted to the thread retracting stud 60.

The needle thread end holder comprises a flat plate 96 mounted toreciprocate from front to rear of the machineacross one end of theneedle slot in the work table. The plate 96 is connected by a pin andslot with one arm of a lever 98 mounted on a pivot 100 carried by thework table. The other arm of the lever 98 is pivotally connected to oneend of a horizontally sliding rod 102 having at its other end a forkedportion 104 surrounding the lower end of a vertically arranged rod 106.The upper end of the rod 106 is pivotally connected to an arm 108 fixedto the shaft 42 operated by the treadle rod 46.

The slot in the work table 6 through which the needle and awl operate islengthened to the left, so that the needle thread end holder may occupya part of the space in the slot without up into the work by the needlein forming the interfering with the needle and 'avvl' lilr-il'l'gsewing. After themachine has stopped, the thread cute i" 'treadle ispartly depressed, and in so domg, the lower en'd -of-"the rod 166,having "an enlargement 1 1i), is moved downwardly against a pawl 1 12pivo'te'd'b'etween the" sides r of the I forked portions 104 on the rod102, the rod- 1116 being he'ld against lateral displacement by a "fixed'bearing 1 14 in the machine. 'The rodl02 is then moved towards theleft, rocking 'tlrie'lever 98 and moving the thread end holder-plate 9"6rearwardly away-from the forward side of the slot in the work table. Iheoperator may then slide the s'hoealong' the work table, so that theneedle thread is moved to the left in'front oft'he threadholde1"-plate.-' 'To again advance and clamp the needle thread'agai-nstthe front wall oif-the slot in the work table, the rod 102 is "moved bythe expansion (if a spring 1 15 surrounding rod 102 and arranged toforce it towards the right.

While the rod 106*is" movi1ig downwardly, the pawl 112 is'held in theposition shown, bya pin 116011 the forked end of the rod 102. When thetreadle is fully depressed the pawl rides over a shoulder at the -end ofthe enlargement 1'10 and-permits the rod 102fto move to the right,clamping the thread. The timing of the mechanisms is such that thethread gripped by the thread holder plate immediately I after the threadcutter has acted, and the thread holder remains yieldingly in clampingposition until the treadleisonce more depressed after sewing of the nextshoe. 'U'p'on releasing the treadle, the end oi" the thread is drawn "by'the pro-per amount past the gripper to guard against the cut endremaining in the machine and becoming held between the work table andthe sole of the next shoe when sewing is begun again. As the treadle rod46 moves upwardly, the rod 1 06 moves with it-and the shoulder onenlargement 110 engages the pair/1 11 2 which is yieldin'gly he'ldin'ahorizontal position by aspiring-1'17. The p'awlis then-rocked to escapethe shoulder on the rodand-the parts are brought back to their startingposition. In.

starting a new=seam, the short end oiffitl-Ie thread held by the needlethread end holder is d-lawn initial stitch where it remains so that notrirm, ming of the'threads is necessary on the leading end of the seam.l f

In the modified form of the invention illustrated in Figures 11 and 1 2,in place o'feinploying aneedle threadend gripper and pulling now-n v thecut end of the needle thread to the level or the work table, a separatecutting device may be provided for severing the leading ond of theneedle thread below the work as a new seam is started. This cuttingdevice comprises a stationary knife 11 8 fixed in the work tableapproximately 1/64 of an inch below its upper surface, the cutting edgeof the knife extending towards the right. A gap is le-ft'be'tween theforward end of the knife 118 and the front side of the slot in the worktable through which the operator may'c'ause the needle thread to pass bymoving the work to the left before actuating the thread cutter blade -22at the-end of the seam. The gap between the knife and the lei-tend ofthe slot in the work table is just large enough to accommodate theneedle thread when it has been moved around the knife so that after thework is removed, the excess of needle thread lies in the work table.With this arrangement, the needle thread p'uller is operated to pull 'asmall amount of from the suppiyloe'fore the knife 22 :operates to severb'oth thr eads, thus providing excess of needle thread which will lie onthe work table when the shoe inoved to the left. excess 'of thread willbe clamped against the table'by the next shoe inserted in the machineand during the first r'e'tracting stroke oftheneedlathe thread passesunder and around the cutting edge of the knife. When the work is fedrelatively to the work table, the thread is 'fercedagains't theouttingedge of the knife and will shear it dfi close to the undersurface of the work. Upon completing the seam when-the thread cutter isactuated in the manner described, -the shoe will be completely releasedwith the-iourthread ends of its seam-trimmed and neat so that it can bepassed to the nextoperator for chamelclosing, levelling or otheroperations without any attention to the thread ends.

Theinature and-scope of the inventionhaving been indioated, and aspecific embodiment of v the several features of the invention havingbeen described, what is claimed is:

l. outsole shoe sewing machine having, in combination, stitchformingdevices including a hook needle and ashu'ttle, a work ta'ble, apresser foot, anda thread cutter comprising a knife edged memberoperating on the machine at'the side of the worl; engaged by thepress'er foot to sever "both threads outside the surface of the work.

2. An outsol'e shoe sewing machine having, "in combination, stitchforming devices indluding a hook needle and ashuttle, a'work table, apresser foot, means for raising the presser foot from ongagementwith thework when the machine is brought to rest, and a thread cutter comprisinga "knife edged member operating on the machine at the side of theworkengaged by the 'pres s'er foot to sever "both threadejwhen the'p'resser foot is disengaged from the work.

3. An outsole shoe sewing mael'iine having, in combination,stitohiorming' devices including a ho'okineedle and "a shuttle, a worktable, a pre'sser "footiengaging'the shuttle side of the work, means forbringing the 'maohine to rest with a loop'of needle thread forming thefinal stitch in a seam remaining above the surface of the work, and athread "cutter arraiiged on the machine to sever the shuttle thread andthe final needle loop while the work "remains supported by the Worktable.

4. Anoutsoleshoe sewing machine having, in combinationpstitchforming'devices including a hook needle and a shuttie, a work table,apre'sser ioo't'engagin'gtheshrittle side of the work, meansforfbr'inging the machine 'torest with a loop of needle thread formingthe final stitch in a seam remaining above the surface of the work, and

means engaging the thread between the shuttle andthe presser foot todeflect the shuttle thread and the'iinal needle loop to one side of theseam and to sever both threads while held by the thread engaging means.

5. An outsole shoe sewing machine having, in combination, "stitchforming devices including a hook needle and a shuttle, a worktable, apresser foot engaging the shuttle side of the work,means for bringingthe machine to rest with a loop of needle thread forming the final"stitch in a seam remaining abovethesurface' of the work, a threadengaging member acting to measure a supply of thread from the shuttle inan amount sufficient for the initial stitch of a new seam, an'da threadcutter arranged to sever the shuttle thread and the 'final needle loopwhen the measuring action or the'thread engaging member is completed.

6. An outsole shoe sewing machine having, in combination, stitch formingdevices including a hook needle and a shuttle, a work table, a presserfoot engaging the shuttle side of the work, means for bringing themachine to rest with a loop of needle thread forming the final stitch ina seam remaining above the surface of the work, a thread engaging memberacting to deflect the shuttle thread and final needle loop to one sideof the seam and simultaneously to measure a supply of thread from theshuttle in an amount suflicient for the initial stitch of a new seam,anda thread cutter arranged to sever the deflected portion of theshuttle thread and final needle loop after the measuring action of thethread engaging member is completed.

7. An outsole shoe sewing machine having, in combination, stitch formingdevices including a hook needle and a shuttle, a work table, a presserfoot engaging the shuttle side of the work, means for bringing themachine to rest with a loop of needle thread forming the final stitchremaining above the surface of the work, a thread cutter comprising anelongated rod having a knife edged end movable lengthwise and laterally,and a member on the thread cutter rod for deflecting the threads towardsthe presser foot when the rod moves lengthwise and for measuring asupply of thread from the shuttle sufficient to form the initial stitchof a new seam when the rod move laterally,

8. An outsole shoe sewing machine having, in combination, stitch formingdevices including a hook needle and a shuttle, a work table, a presserfoot engaging the shuttle side of the work, means for bringing themachine to rest with a loop of needle thread forming thefinal stitch ina seam remaining above the surface of the work, a thread cuttercomprising an elongated rod having a knife edge at one end mounted onthe machine to move towards and from the work, a member slidinglymounted on the rod for deflecting thethread into a position at one sideof the seam where it may be severed by the cutter edge, and resilientmeans connecting the rod and the thread deflecting member to permit thedeflecting member to yield as the cutter severe the thread.

9. An outsole shoe sewing machine having, in combination, stitch formingdevices including a hook needle and a shuttle, a work table, a presserfoot engaging the shuttle side of the work, means for bringing themachine to rest with a loop of needle thread forming the final stitch ina seam remaining above the surface of the work, a thread cutter actingagainst the surface of the work to sever the threads, and a threaddeflecting member arranged to hold the needle loop and the shuttlethread at one side of the seam in the path of movement of the threadcutter.

10. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser foot engaging the shuttle side of the work, means for bringingthe machine to rest with a loop of needle thread forming the finalstitch in a seam remaining above the surface of the work, a threadcutter comprising an elongated rod having a knife edged end movablelengthwise and laterally, a member on the thread cutter rod fordeflecting the threads towards the presser foot when the rod moveslengthwise and for measuring a supply of thread from the shuttlesuflicient to form the initial stitch of a new seam when the rod moveslaterally, and means for adjusting the amount of lateral movement of thethread cutter rod before the thread is cut to regulate the length ofthread measured from the shuttle.

11. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a-shuttle, a work table, apresser foot engaging the shuttle side of the work, means for bringingthe machine to rest with a loop of needle thread forming the finalstitch in a seam remaining above the surface of the work, a threadengaging member acting to deflect the shuttle thread and final needleloop against the pressor foot, a thread cutter arranged to sever thethreads in deflected positions, and means on the presser foot forholding the severed end of the shuttle thread remaining in the machineto insure proper formation of the initial stitch of a new seam.

12. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser footengaging the shuttle side of the work, means for bringingthe machine to rest with a loop of needle thread forming the finalstitch in a seam remaining above the surface of the work, a threadcutter for severing the needle loop close to said surface of the work,and means arranged to draw the severed end of the needle threadconnected to the supply down to the level of the work table.

13. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser foot engaging the shuttle .side of the work, means for bringingthe machine to rest with a loop of needle thread forming the finalstitch in a seam remaining above the surface of the work, a threadcutter for severing the needle loop close to said surface of the work, aretracting device arranged to draw the severed end of the needle threadconnected to the supply down to the level of the work table, and meanson the work table for holding the end of the needle thread at a positionto insure the formation of the initial stitch in a new seam with the endclose to the work.

14. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser foot engaging the shuttle side of the work, means for bringingthe machine to rest with a loop of needle thread forming the finalstitch in a seam remaining above the surface of the work, a threadcutter arranged to sever both threads close to said I surface of thework, means on the presser foot for holding the severed end of theshuttle thread, and a gripper on the work table for holding the end ofthe needle thread remaining in the machine at a position after the workis removed to insure proper formation of the initial stitch in a newseam.

15. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser foot engaging the shuttle side of the work, means for bringingthe machine to rest with a loop of needle thread forming the finalstitch in a seam remaining above the surface of the work, a threadcutter arranged to sever both threads close to said surface of the work,means on the presser foot for holding the severed end of the shuttlethread, a retracting device arranged to draw the severed end of theneedle thread connected to the supply down to the level of the Worktable, and means on the work table for holding the end of the needlethread remaining in the machine at a position after the work is removedto insure the formation of the initial stitch in a new seam with the endof the needle thread close to the work.

16. An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser foot engaging the shuttle side of the work, means forbringing'the machine to rest with a loop of needlethread forming thefinal stitch in a seam remainingabove the surface of the work, a threadcutter arranged to sever both threads close to said surface of the work,means on the presser foot for holding the severed end of the shuttlethread, and means on the work table for holding the end of the needlethreadremaining in the machine at a position'after the work is removedto insure prop er formation of the initial stitch in a new seam memberarranged to sever both threads close to the surface of the work engagedby the presser foot, a retracting device for drawing the severed.

end of the needle thread down to the level of the work table, andactuating means movable in one direction for operating the thread cutterto sever the thread, andin the other direction for causing theretracting device to withdraw thread.

18. An outsole shoe sewing machine having,

in combination, stitchforming devices including a hook needle and ashuttle, a work table, a presser foot, a thread cutter comprising aknife edged member arranged to sever both threads close to the surfaceof the work engaged by the presser foot, a retracting device for drawingthe severed end of the needle thread'down to the level of the worktable, a treadle actuated rod connected to the thread cutter and theretracting device for operating the thread cutter to sever the threadswhen moved in one direction and for causing the retracting device towithdraw and release thread when moved in the other direction.

19; An outsole shoe sewing machine having, in combination, stitchforming devices including a hook needle and a shuttle, a work table, apresser foot, avthread cutter comprising a knife edged member arrangedto sever both threads close to the surface of the work engaged by thepresser foot, a retracting device for drawing the severed endof theneedle thread down tothe level of the work table, a gripper on the worktable for holding the end of the needle thread remaining in the machineto insure the proper formation of the initial stitch in a new seam, andmeans movable in one direction to cause the gripper to open and thecutter to sever the threads, and in v the other direction to cause theretracting device to withdraw thread.

JOSEPH GOULDBOURN.

